Protecting apparatus for electrical machines and plants.



N0. 703,l53. Patented June 24, i902.

P. RUDHARBT.

PROTECTING APPARATUS FOR ELECTRICAL MACHINES AND PLANTS.

' (Application filed July 23, 1901.)

(No Model.)

m YEA/TOR UNITED STATES PATENT OFFICE.

PAUL RUDHARDT, OF GENEVA, SWITZERLAND.

PROTECTING APPARATUS FOR ELECTRTCAL MACHINES AND PLANTS.

SPECIFICATION forming part of Letters Patent No. 703,153, dated June 24, 1902.

Serial No. 69,35 9. (N model.)

To all whom it may concern.- h, and a contact-lug or body portion from Be it known that I, PAUL RUDHARDT, engiwhich said arms project. The inner arm g neer, a citizen of the Republic of Switzerland, of each head is so formed as to fit over one residing at Grand Pr,No.30,Geneva,Switzerend of the tube a, and for clamping such arm land, have invented 21. Protecting Apparatus to the tube the arm is split and provided for Electrical Machines and Plants, of which with a clamping-screw for clamping the two the following is a specification. parts together around the tube end, as clearly The object of thisinvention is to provide a shown in the figures.

reliable and conveniently operated and in The outer arm 71, of each head is provided to spected lightning-arrester; and the invention in line with the shank of the respective piston consists of a lightning-arrester comprising a with a bore adapted to receive the same, and tubular body of insulating material, pistons the shank of the piston is of such length as in said body and provided with shanks extendto enter the bore when a suitable quantity of ing out of the same, a mass of mixed pulverthe mass described is located in the tube t.

t5 ized conducting and non-conducting material Set-screws Z, seated in the arm 7, engage in said tubular body between the pistons, the shank of the piston, By this engagecontact-heads, one at each end of the tubular ment of the inner arm with the end of the body and provided each with an inner and tube and the engagement of the outer arm an outer arm, means for clamping the inner with the shank of the piston the contacto arm of each head to one end of the tubular heads serve for locking the pistons immovbody, means securing the shanks of the pisably in position at any desired point in the tons, respectively, to the outer arms of the tube. heads at opposite ends of the body, contact- Two spring-clamps c of like construction lugs on said body, and spring-clamps adapted are adapted to receive the contact-lugs, re-

25 to receive said lugs. spectively, of the contact-heads, as clearly 7 5 In the accompanying drawings, Figure 1 shown in Figs. 1 and 3, whereby the device is is a side elevation, partially in vertical secsupported. These clamps permit ready retion, of my improved lightning-arrester. Fig. moval of the device for inspection or for elimi- 2 is a front view of a portion of the arrester. nating it from the circuit entirely. For in- 30 Fig. 3 is a top view of the portion shown in specting the arrester it is only necessary to Fig. 2, and Figs. 4 and 5 show in diagram withdraw the device from the clamps c and two suitable connections of the device for release the screw which holds the split inner use. arm of the one contact-head clamped upon Similar letters of reference indicate correthe tube i. The head, with the piston at 35 spending parts. tached, may then be withdrawn, the piston Referring to the drawings, 6 indicates a passing out of the tube t' and permitting a tubular body of suitable insulating material, complete inspection of the interior to the such as porcelain. Within the body is 10- other piston. cated a mass composed of a mixture of con- Conducting-wires c and f are attached to 40 ducting and non-conducting fire proof matesuit-able lugs 61, which make contact with rial, such as pulverized hard coal and pulclamps c, and said lugs and clamps are supverized magnesia. This mass is retained in ported, respectively, on theinsulating mounts the tube by means of two pistons o and 19. ct and Z).

The piston o is provided with a shank a, Figxtillustrates the application ofthelight- 45 which extends from one end of the tube, and ning-arrester to an ordinary line-wire. o is the piston 19 with a shank m, extending from the line-wire; i, the lightning-arrester; q, a the other end of the tube. To each end of tube containing one or more fusible wires, the tube is applied a contact-head. These and 3 indicates an earth-plate. heads are of like construction and are com- In Fig. 5, 1' indicates the line; L, a motor in- 50 posed each of an inner arm 7, an outer arm sorted on the line. 'i and q are respectively the lightning-arrester and a fuse-tube, as in Fig. 4, which are located in a shunt u of the line.

WVhen a lightning discharge strikes the linewire 1', Fig. 4, it passes off at once into the earth through the lightning-arrester, fusetube, and plate .9 and does not pass to the machine connected with the wire 1'. The current ordinarily passing over the wire 0' from or to the machine connected therewith is not of sufficiently high voltage to bridge the space between the conducting and non-conducting particles of the mass 70, and consequently does not pass to earth. The lightning-arrester has no effect, therefore, upon the current ordinarily flowing over the line. Should said current, however, by accident due to any cause pass the lightning-arrester,it will immediately melt the fuse-wires in the fuse-tube g, which will stop the escape of said line-current to earth.

When a lightning discharge strikes the line 7', Fig. 5, it is conducted through the shunt L6, and the machine '15 is not endangered. The main-line current coming over the wire 0, however, cannot pass the lightning-arrester and flows through the motor '6. Should said line-current by any means pass the lightningarrester, it will melt the fuse in the fuse-tube g, thereby immediately opening the shunt and preventing further passage of the linecurrent therethrough.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- A lightningarrester consisting of a tubular body of insulating material, pistons in said body and provided with shanks extending out of the same, a mass of mixed pulverized conducting and non-conducting material in said tubular body between the pistons, contact-heads, one at each end of the tubular body and provided each with an inner and an outer arm, means for clamping the inner arm of each head to one end of the tubular body, means for securing the shanks of the pistons respectively to the outer arms of the heads, at opposite ends of the body, contact-lugs on said heads, and spring-clamps adapted to receive said lugs, substantially as set forth.

In testimony that I claim the foregoing as my invention l have signed my name in presence of two subscribing witnesses.

PAUL RUDUARDT.

W'itnesses:

E. IMER-SOHNEIDER, L. It. MUNIER. 

